CS 106, Winter 2009 Class 1, Section 4

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CS 106, Winter 2009Class 1, Section 4

Slides by: Dr. Cynthia A. Brown, cbrown@cs.pdx.eduInstructor section 4: Dr. Herbert G. Mayer, herb@cs.pdx.edu

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Class Basics• Prerequisites• Exams, grades• Labs• Textbooks, thumb drive• Policies• Contact info• Website (Blackboard)• All information is available in the syllabus on the

Blackboard site. Go to http://psuonline.pdx.edu and login using your Odin account.

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The Blackboard Site

• We’ll take some time after the break to get oriented to the Blackboard site.

• If you do not have your Odin account and password yet, take care of it right away at the Help Desk (SMU basement)

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Class Goals(Why am I taking this class?)

• The main goal of this class is to teach you problem-solving skills.

• We will focus on visual approaches to problem solving.• You can only do so much in the abstract, so…• As a medium for solving problems, we’ll learn some

Visual Basic (VB).• There is way more to VB than we can cover. If you like

it, the text will help you learn more… or, you can take another programming class (CS 161).

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Problem Solving

• The Dan Roam text, “The Back of the Napkin,” (BN) is our main source for general problem-solving material. (Also see http://www.digitalroam.com)

• Roam analyzes problem types and discusses visual approaches to solving them.

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The BN Premise

• Any problem can be made clearer with a picture.– “Pictures can represent complex concepts and

summarize vast sets of information in ways that are easy for us to see and understand.”

• You do NOT have to be an artist to use this approach!– This is about thinking, not pretty pictures.

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Thinking

• We’ll learn a thinking process for attacking a problem

• We’ll learn a bit of logic and some visual techniques to help us with the process

• We’ll practice our techniques in the realm of VB programming

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The Four Steps of Visual Thinking

• Look: gather the data• See: understand what you’re looking at, find

what is relevant or useful• Imagine: come up with ideas• Show: communicate the ideas or embody

them in action

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The Process

SHOW

IMAGINE

LOOK SEE

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A Simple Example: Crossing the Street

• Look: Gather information: amount of traffic, traffic lights, sirens?

• See: How does traffic work. Do people stop for lights? Pedestrians?

• Imagine: What if I jaywalk? What if I walk to the corner and cross?

• Show: Cross the street safely.

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Crossing a Normal Street

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Crossing a Street in HCM City

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The Arc de Triomphe

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Getting to the Arc de Triomphe

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And the moral is…

• Follow the process!• Don’t just jump in and start trying something:

it could be dangerous!• For our purposes, this means: take the time to

analyze the problem before you start constructing the solution. In the end you will have a better solution in less time.

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Let’s take a closer look at some of these steps…

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Look: Collect and Screen

• Scan the environment to build up a big-picture sense of things

• Ask questions to fill in any gaps• Make an initial effort to understand:– What is important?– What are the fundamental coordinates of the

data?– Is this what you expected to see? Or do you need

to make an additional effort to understand?

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The Four Steps of Looking

• In physical looking– Orientation: up and down– Position: where am I in the scene?– Identification: what am I looking at here?– Direction: focusing on something important

• The same process holds when looking at a chart or other picture.

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A Typical Chart

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_x0006_ 20-29

_x0006_ 30-39

_x0006_ 40-49

_x0006_ 50-59

_x0006_ 60-69

_x0008_ 70 plus

_x0005_ skip

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Age of Members

Orientation, Position, Identification, Direction

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To Look at Data

• Collect everything relevant• Lay it out where you can see it all (garage sale

principle)• Identify the type of data• Define a coordinate system to give orientation

and direction• Practice visual triage

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Type of Data: The Six Questions

• Who and what?• How much?• When?

(even fore pure math problem?)

• Where?• How?• Why?

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Coordinate System

• Use the six questions (who/what, how much, where, when, how, why) to develop a coordinate system:– For example, compare who to how much (bar

chart or pie chart)– Or make an axis for what versus how much, and

plot in who.– A stock price chart compares how much to when– Etc.

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Visual Triage

• Pare down the information to just what is relevant

• Present it in a way that takes advantage of the visual system’s built-in processing

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Example: Which way is up?

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Example: What Not to Step On

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What We Notice

• Proximity: Things that are close together are related

• Color: We notice color right away and assume grouping based on color

• See page 72 for others

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Looking versus Seeing

• Looking is about colleting the raw information and trying different ways of arranging it

• Seeing is about selecting what’s important

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See: Select and Clump

• Which inputs are worth more attention?• Do you recognize any patterns?• Do you understand this environment well

enough to make decisions about it?• Or do you need to go back for more data?

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Six Ways to See

• The six ways to see correspond to the six questions (who/what, how much, when, where, how, why).

• The trick is to organize things in a way that makes the information apparent.

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Example: Seeing the Market

These charts show how much versus when.

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Example: Timeline

Timeline shows who/what versus when.

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US History Timeline

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Map: What vs Where

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Recall The Process

SHOW

IMAGINE

LOOK SEE

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Imagine: See What Isn’t There

• Can you make analogies to things you’re familiar with?

• Can you rearrange the patterns you see to make more sense?

• Can you manipulate the patterns so something invisible becomes visible?

• Is there a hidden framework connecting everything you saw?

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Imagining Activities

• Get all the inputs in mind, then close your eyes and see if new patterns emerge.

• Find analogies.• Manipulate the patterns, and see if something

new becomes visible.• Alter the obvious: find multiple ways to show

the same thing.

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Example: History

• Do economic upheavals lead to wars and revolutions? We might think of such an idea when studying historical timelines.

• Did you know there was a major recession, with high energy prices, just before the Civil War?

• Studying timelines might give us ideas for other correlations. (Possibly silly ones.)

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Show: Make it All Clear

• What are the three most important pictures that emerged?

• What visual framework is most appropriate for sharing what I’ve seen?

• Check against your original data: does your idea make sense?

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Six Frameworks for Showing

• Who/what: qualitative representation: portrait• How much: quantitative representation: chart• Where: position in space: map• When: position in time: timeline• How: cause and effect: flowchart• Why: deduction and prediction: multi-variable chart

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ManyEyes: A Great Resource

• Find it at http://services.alphaworks.ibm.com/manyeyes/

• It has great resources for creating fancy charts and graphs.

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BREAK

10 min

Demonstration

Getting into Blackboard